Volley AppController class object returning null

Question

I am making an app that makes a JsonObjectRequest and retrieves a JSON data from an URL using the Volley Networking Library for android.

AppCon

Answer 1

i think you should create the "AppController" like this :

public class AppController {

    private static AppController mInstance;

    private RequestQueue mRequestQueue;

    private static Context mCtx;

    private AppController(Context context){
        mCtx = context;
        mRequestQueue = getRequestQueue();
    }

    public static synchronized AppController getInstance(Context context) {
        if (mInstance == null) {
            mInstance = new AppController(context);
        }
        return mInstance;
    }

    public RequestQueue getRequestQueue() {
        if (mRequestQueue == null) {
            mRequestQueue = Volley.newRequestQueue(mCtx.getApplicationContext());
        }
        return mRequestQueue;
    }

    public  void addToRequestQueue(@NonNull final Request request) {
        getRequestQueue().add(request);
    }

    public  void addToRequestQueueWithTag(@NonNull final Request request, String tag) {
        request.setTag(tag);
        getRequestQueue().add(request);
    }
}

and the MainActivity.class

//adding request to the RequestQueue
AppController.getInstance(this).addToRequestQueue(jsonObjReq);